1. Field
Apparatuses and methods consistent with exemplary embodiments relate to a digital broadcast transmitter, a digital broadcast receiver, and methods for constructing and processing streams thereof, and more particularly, to a digital broadcast transmitter for generating and transmitting a transport stream including normal data and mobile data, a digital broadcast receiver for receiving and processing the transport stream, and methods thereof.
2. Description of the Related Art
As digital broadcasting is propagated, various electronic devices support a digital broadcast service. In particular, recently, other than devices such as a digital broadcast TV and a set-top box in the house, portable devices of the individual, for example, a mobile phone, a navigation device, a personal digital assistant (PDA), a portable multimedia player (e.g., an MP3 player), etc., have a function for supporting the digital broadcast service.
Hence, digital broadcast standards for providing the digital broadcast service to the portable devices are under discussion.
Among them, an ATSC-Mobile/Handheld (MH) standard has been discussed. The ATSC-MH standard describes a technique for placing and transmitting mobile data in a transport stream for carrying data for a related art digital broadcast service, that is, normal data.
Since the mobile data is data received and processed by the portable device, the mobile data is processed robustly against errors, compared to the normal data, because of the mobility of the portable device and is included in a transport stream (TS).
FIG. 1 is a diagram of an example of a TS including the mobile data and the normal data.
Section (A) of FIG. 1 depicts the stream in which the mobile data and the normal data each are placed and multiplexed in their allocated packets.
The stream of section (A) of FIG. 1 is converted to a stream of section (B) of FIG. 1 through interleaving. Referring to section (B) of FIG. 1, mobile data (MH) can be divided to a region A and a region B according to the interleaving. The region A indicates a region within a certain range based on aggregation of the mobile data over a certain size in a plurality of transmission units, and the region B indicates a region excluding the region A. The division into the region A and the region B is merely exemplary, and may be differently divided in some cases. That is, in section (B) of FIG. 1, the portion not including the normal data may be set to the region A, and the portion corresponding to the transmission unit including the normal data may be set to the region B.
Meanwhile, compared to the region A, the region B is relatively vulnerable to error. That is, the digital broadcast data can include known data, for example, a training sequence which is properly demodulated and equalized by a receiver for error correction. According to the related art ATSC-MH standard, the region B does not include the known data and thus is vulnerable to the error.
Due to the stream structure of FIG. 1, the transmission of the mobile data can be limited. That is, while broadcasting stations and devices supporting the mobile broadcast service gradually increase, efficiency degradation of the stream occurs because the portion allocated to the normal data is unavailable in the stream as constructed in FIG. 1.
Hence, a technique for efficiently using the structure of the transport stream is demanded.